Browsing by Author "Chuang, JC"

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Effects of thermal N-2 annealing on passivation capability of sputtered Ta(-N) layers against Cu oxidation
(1998-11-01)
Chuang, JC
;
Chen, MC
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
The effects of thermal N-2 annealing on the passivation capability of sputtered Ta and Ta-nitride [Ta(-N)] layers against Cu oxidation in a 200 Angstrom Ta(-N) covered Ta(-N)/Cu/SiO2/Si structures was investigated. The N-2 annealed Ta layers revealed degradation in passivation capability, presumably due to grain growth of the Ta passivation layer. In contrast, the nitrogen-doped Ta-nitride layers showed a contrary trend. For the Ta-nitride layer with 23.5 atom % of nitrogen, passivation capability was effectively improved by N-2 annealing at 300 degrees C. For the Ta-nitride layer with 30.5 atom % of nitrogen, N-2 annealing at higher temperatures (500-700 degrees C) was necessary to improve the passivation capability. The healing of sputtering damage of Ta-nitride passivation layers by the thermal N-2 annealing was responsible, presumably, for the improvement of passivation capability.
Effects of thermal N-2 annealing on passivation capability of sputtered Ta(-N) layers against Cu oxidation
(1998-11-01)
Chuang, JC
;
Chen, MC
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
The effects of thermal N-2 annealing on the passivation capability of sputtered Ta and Ta-nitride [Ta(-N)] layers against Cu oxidation in a 200 Angstrom Ta(-N) covered Ta(-N)/Cu/SiO2/Si structures was investigated. The N-2 annealed Ta layers revealed degradation in passivation capability, presumably due to grain growth of the Ta passivation layer. In contrast, the nitrogen-doped Ta-nitride layers showed a contrary trend. For the Ta-nitride layer with 23.5 atom % of nitrogen, passivation capability was effectively improved by N-2 annealing at 300 degrees C. For the Ta-nitride layer with 30.5 atom % of nitrogen, N-2 annealing at higher temperatures (500-700 degrees C) was necessary to improve the passivation capability. The healing of sputtering damage of Ta-nitride passivation layers by the thermal N-2 annealing was responsible, presumably, for the improvement of passivation capability.
Formation of Cr-O and Cr-N-O films serving as Cu oxidation resistant layers and their N-2 pre-sintering effect
(1998-12-14)
Chuang, JC
;
Chen, MC
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
This study investigates the Cu oxidation resistant layers of sputter deposited Cr-O and reactively sputter deposited Cr-N-O of 200 Angstrom thickness. with and without, thermal N-2 pre-sintering treatment. The resistance against Cu oxidation (or the highest annealing temperatures without causing Cu oxidation) of the Cr-O and Cr-N-O covered Cu films were found to be 350 and 500 degrees C, respectively, in an O-2 ambient. The inherent defects in the Cr-O lavers and the nitrogen doping in the Cr-N-O layers were believed to be the principal causes for the distinction of the resistance against Cu oxidation. With Na pre-sintering treatments on the Cr-O or Cr-N-O covered Cu films, the ability of resistance against Cu oxidation was degraded. The higher the N-2 pre-sintering temperature was, the lower the oxidation temperature of Cu became. The N-2 pre-sintering thermal process led to formation of defects on the Cr-O and Cr-N-O layers, resulting in the degradation of the ability of resistance against Cu oxidation. Thus, the application of Cr-O or Cr-N-O as a resistant layer against Cu oxidation should avoid such an excess thermal treatment. (C) 1998 Elsevier Science S.A. All rights reserved.
Formation of Cr-O and Cr-N-O films serving as Cu oxidation resistant layers and their N-2 pre-sintering effect
(1998-12-14)
Chuang, JC
;
Chen, MC
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
This study investigates the Cu oxidation resistant layers of sputter deposited Cr-O and reactively sputter deposited Cr-N-O of 200 Angstrom thickness. with and without, thermal N-2 pre-sintering treatment. The resistance against Cu oxidation (or the highest annealing temperatures without causing Cu oxidation) of the Cr-O and Cr-N-O covered Cu films were found to be 350 and 500 degrees C, respectively, in an O-2 ambient. The inherent defects in the Cr-O lavers and the nitrogen doping in the Cr-N-O layers were believed to be the principal causes for the distinction of the resistance against Cu oxidation. With Na pre-sintering treatments on the Cr-O or Cr-N-O covered Cu films, the ability of resistance against Cu oxidation was degraded. The higher the N-2 pre-sintering temperature was, the lower the oxidation temperature of Cu became. The N-2 pre-sintering thermal process led to formation of defects on the Cr-O and Cr-N-O layers, resulting in the degradation of the ability of resistance against Cu oxidation. Thus, the application of Cr-O or Cr-N-O as a resistant layer against Cu oxidation should avoid such an excess thermal treatment. (C) 1998 Elsevier Science S.A. All rights reserved.
Passivation of Cu by sputter-deposited Ta and reactively sputter-deposited Ta-nitride layers
(1998-09-01)
Chuang, JC
;
Chen, NC
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Sputter-deposited tantalum (Ta) and reactively sputter-deposited Ta-nitride films were studied with respect to the passivation capability against copper (Cu) oxidation in thermal O-2 ambient. A 200 Angstrom Ta or Ta-nitride film was sputter-deposited on a 2000 Angstrom Cu film using a Ta target in an Ar/N-2 gas mixture. With Ta passivation, Cu was not oxidized at temperatures up to 400 degrees C, which can be further improved by using passivation of an amorphous Ta-nitride film deposited in an appropriate condition. The absence of long-range defects in the Ta-nitride film was presumably responsible for this improvement. However, sputtering-induced surface damage by excess N-2 in the sputter gas mixture may reduce the passivation capability of Ta-nitride films. When the passivated Cu was oxidized, the Cu oxides always resided in the top sur face region. That is, in the oxidation process, Cu diffused through the defects of the passivation layers to the outer surface.
Properties of sputtered Cr-O and reactively sputtered Cr-N-O as passivation layers against copper oxidation
(1998-11-01)
Chuang, JC
;
Chen, MC
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Passivation layers of 200 Angstrom sputtered Cr-O as well as reactive sputtered Cr-N-O were studied with respect to the passivation capability against thermal oxidation of Cu in flowing nitrogen and flowing oxygen ambients. In a flowing N-2 ambient, both Cr-O and Cr-N-O passivation layers were able to prohibit oxidation of Cu at temperatures up to 700 degrees C. In an O-2 ambient, the passivation capability of Cr-N-O layer was found to be 500 degrees C, which is 150 degrees C higher than that of Cr-O layer. The superiority of the passivation capability of the Cr-N-O layer is presumably due to decoration of the surface defects and grain boundaries with nitrogen, which provide fast paths for oxygen and copper diffusion. (C) 1998 American Vacuum Society. [S0734-211X(98)11706-7].
Properties of sputtered Cr-O and reactively sputtered Cr-N-O as passivation layers against copper oxidation
(1998-11-01)
Chuang, JC
;
Chen, MC
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Passivation layers of 200 Angstrom sputtered Cr-O as well as reactive sputtered Cr-N-O were studied with respect to the passivation capability against thermal oxidation of Cu in flowing nitrogen and flowing oxygen ambients. In a flowing N-2 ambient, both Cr-O and Cr-N-O passivation layers were able to prohibit oxidation of Cu at temperatures up to 700 degrees C. In an O-2 ambient, the passivation capability of Cr-N-O layer was found to be 500 degrees C, which is 150 degrees C higher than that of Cr-O layer. The superiority of the passivation capability of the Cr-N-O layer is presumably due to decoration of the surface defects and grain boundaries with nitrogen, which provide fast paths for oxygen and copper diffusion. (C) 1998 American Vacuum Society. [S0734-211X(98)11706-7].
Properties of thin Ta-N films reactively sputtered on Cu/SiO2/Si substrates
(1998-06-08)
Chuang, JC
;
Chen, MC
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
This work studied the thin film properties of 200 Angstrom Ta and Ta-N films reactively sputtered on the Cu/SiO2/Si substrates. The nitrogen atomic concentration in the Ta-N film was found to saturate at about 30%. Excessive sputtering gas flow, especially the N-2 gas, caused surface damage to the sputter deposited films. Thermal annealing in N-2 ambient at temperatures up to 700 degrees C did not change the atomic concentrations and the chemical states of Ta and N in the Ta and Ta-N films. The thermal annealing resulted in the grain growth and the healing of sputter damage, but it also induced new defects in the Ta-N films due to thermal stress. This presents a reliability problem in process application involving high temperature thermal cycle. (C) 1998 Elsevier Science S.A. All rights reserved.
Quadtree-segmented image compression method using vector quantization and cubic B-spline interpolation
(2004-06-01)
Chang, CC
;
Chuang, JC
;
Chung, CY
;
資訊工程學系
;
Department of Computer Science
A novel hybrid image compression method based on quadtree is proposed, involving two techniques: vector quantization (VQ) and cubic B-spline interpolation. Traditional block-based image compression methods, such as VQ, block truncation coding and others, do not take the relationship of neighbouring blocks into consideration, which results in a limit to their compression rate. To put it another way, if the relationships between neighbouring blocks can be included in the scheme by application of the quadtree technique and the VQ method, as well as cubic B-spline interpolation, which is exactly what is attempted in this paper, the performance of image compression can be improved significantly. According to the experimental results, this method can achieve satisfactory results in terms of the compression rate, while maintaining an acceptable image quality compared with block-based image compression methods.
Sputtered Cr and reactively sputtered CrNx serving as barrier layers against copper diffusion
(1998-12-01)
Chuang, JC
;
Tu, SL
;
Chen, MC
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
The barrier capability of sputter deposited Cr and reactively sputter deposited CrNx films against Cu diffusion in a structure of Cu/barrier/p(+)n junction diodes was investigated by means of thermal annealing at elevated temperatures in conjunction with electrical measurements and material analysis. For a 500 Angstrom thick barrier layer, the barrier capability of a pure Cr layer was limited to temperatures up to 500 degrees C, while CrNx films sputter deposited in a gas mixture of Ar and N-2 showed improved barrier capabilities. With Ar/N-2 flow rates of 24/6 to 24/12 standard cubic centimeters per minute, the deposited CrNx films possessed a much improved barrier capability. In particular, the Cu/CrNx (24/9)/p(+)n junction diodes were capable of sustaining 30 min of thermal anneal at temperatures up to 700 degrees C without degradation of the diodes' electrical characteristics. The failure of Cu/Cr/p(+)n and Cu/CrNx/p(+)n junction diodes under extreme thermal treatment was presumed to arise from two mechanisms: grain boundary diffusion for lightly nitrogen doped CrNx and pure Cr barriers, and localized defect (microcrack) diffusion for excessively nitrogen doped CrNx barriers.